This is one of those blog posts where I’m trying to walk through my thinking on an awkward subject, and it may end up wandering around quite a bit as I try to avoid various land mines, but typing it out might help clarify things in a way that will let me move forward.

So, the Nobel Prize in Physics will be announced on Tuesday, and a lot of people are playing guess-the-laureate(s). One possible winning subject that comes up a lot is “slow light” with at least part of the prize going to Lene Hau. And I’m kind of conflicted about the idea, leading to this blog post…

On the one hand, I absolutely agree with the many people who say it’s long past time for a physics Nobel to go to a woman. It’s an absolutely travesty that they never honored Mildred Dresselhaus or Vera Rubin when they had the chance, and only slightly less bad that they didn’t honor Deborah Jin. A Nobel award to Hau would be a tiny step toward correcting that shameful history.

On the other hand, though, I’m not super excited about this specific topic as a means to address that problem. I was a grad student at the time that Hau’s first papers got a huge amount of media attention, and the reaction at the time was that this is the prototypical example of a science story that’s way more impressive to science writers than actual scientists. There hasn’t been a lot in the last twenty-ish years to change that impression, for me.

This is not to say that there’s anything wrong with the science– it’s good, solid, technically demanding work that absolutely does what it says: the propagation of light through some medium is slowed or even stopped for a time by the interaction between the light and the medium. It’s just that what it does is a better hook for headline writers than for anything else. “Scientists slow light to 1 m/s!” certainly catches the eye, but explaining how it’s done is really difficult (the interaction between multiple laser fields in a cloud of multi-level atoms creates a situation where the effective index of refraction is changing very rapidly in a way that makes a pulse propagate very slowly through that medium), and the claims of what it’s good for remain really far out. There’s certainly a community of people that work on these systems, but it’s still kind of a niche thing– there are people who work on this stuff, but nobody’s really using “slow light” systems as a tool to study other phenomena, in the way that things like laser cooling, Bose-Einstein Condensation, or even femtosecond frequency combs have become common components of experimental systems.

Comparing “slow light” to some of the other frequently-suggested topics doesn’t really look great: quantum information comes up a lot, and that’s a field that has absolutely exploded since the work of frequently-suggested laureates Alain Aspect and John Clauser, with a lot of the field’s progress driven by their regularly-suggested co-laureate Anton Zeilinger. There are a lot of proposals for the theoretical work on geometric phases done by Yakir Aharonov and Michael Berry, which I don’t understand as well as I ought to, but which has become central to a lot of theory– “Berry’s phase” is a phrase that occurs with great regularity across a huge range of AMO and condensed matter physics. Perovskite solar cell materials and “metamaterial” systems also come up a lot, and those are a bit outside my expertise but both seem to have spawned larger and more active research communities than “slow light.”

The suggestion of “slow light” also doesn’t feel like a terribly well-thought-ought proposal, in that the only name ever mentioned is Hau’s. The basic ideas are a fairly straightforward application of the larger subject of “electromagnetically induced transparency” in gases of multi-level atoms, which was a thing before Hau’s headline-grabbing work, and continues to be carried on by lots of other groups. A prize for that general area of work might be in order, but if you’re going to propose that, there should be other names attached– Steve Harris and Marlan Scully, probably? Citing only Hau doesn’t suggest that this is a proposal based on familiarity with the overall body of Nobel-worthy physics, but more that she’s one of the few women to make headlines in physics research, and so readily comes to mind when writers have to draw up lists of possible laureates.

So, as I said, I’m conflicted. A prize for “slow light” shared by Hau wouldn’t be a travesty, but it’s not close to the most important of the areas that have yet to be honored, even on the AMO side of physics. At the same time, even a tiny step toward correcting the gender imbalance would be very much a Good Thing. I wouldn’t be angry if it turns out to be the subject of this year’s Nobel, but I’m not fired up about it in a way that would get me to lobby the Swedish Academy for this specific award (as I would’ve for Rubin or Dresselhaus or Jin, were they still alive).

Ultimately, what this points to is a need to develop a deeper bench of women who might be candidates for the Nobel Prize in Physics. This means not just recruiting and promoting women within physics, but also digging a bit deeper on the writing/communication side to develop a knowledge of who’s doing good work that isn’t getting headlines.